Fiberglass window plug

[Semaphore]

I'm converting my charger to a daytona using a Janak kit
Can a fiberglass plug be fitted with out cracking.

[Stevearino]

Bottom line is there will always be a different rate of expansion between the steel and the fiberglass so cracking will be a risk. If it were a Superbird and you were putting a vinyl roof on it might get away with it but it still might telegraph through the material. Using a glass nose or wing works  well because there is always a defined seam or break between the steel body and the glass part.

[Street Teacher]

I have a vega hatch complete for sale. $250.00 in ioa. Phone #515-943-2000 ask for stan

[Daytona R/T SE]

I'm converting my charger to a daytona using a Janak kit
Can a fiberglass plug be fitted with out cracking.

The Janak fiberglass Daytona rear window plug makes an excellent three dimensional pattern

for fabricating your own in steel.



Mine:

[Street Teacher]

I also have a janek plug and window plus trunk close out. Panel Stan in Iowa. 515-943-2000

[daytonalo]

I would like to hear Larry Hotrod to chime in as I believe I read he used a fiberglass pug and he does not have vinyl top .

[Daytona R/T SE]

I would like to hear Larry Hotrod to chime in as I believe I read he used a fiberglass pug and he does not have vinyl top .

Larry used a vega.

[Daytona R/T SE]

Some guys have had good luck with the Fiberglass plugs.

If I ever get around to doing my Charger 500 clone, I was going to attempt to use the fiberglass one I have.

It will have a race car theme to it, radiused wheel wheels, etc. so a crack or two really wouldn't matter on this one.

[DAY CLONA]

I'm converting my charger to a daytona using a Janak kit
Can a fiberglass plug be fitted with out cracking.

If your going to go with the fiberglass plug, which IMHO and from experience will EVENTUALLY crack at the bond sites, best thing to do BEFORE you put the plug in is: welded in frame connectors, the type that pass thru the floor, weld/re weld every inch of the unibody, not continuous welds, but improve upon the factory spaced welds in quality, as these cars were haphazardly welded on the line, when you install the plug were the "lips" contact the inner sail panels, 24-36 grit finish on both the steel and the glass for tooth, do not use SMC, or similar Vette panel adhesive, use Marson MarGlas long strand polyester filler, but fit the panel first, use screws to align the panel flanges to the sail panels, that will give you a go-no go fit when you are in a hurry before the MarGlas set-ups (15mins), so lather the panels flanges up, you and an assistant quickly install the panel, don't draw the screws too tight, let it set up for a day or so, then remove the screws, then use a flap wheel, 24-36 grit to put a bevel/taper around the outer sides and top of the panel, as well as put some tooth on the surrounding steel, then use an EPOXY fiberglass resin and MAT (not cloth), with EPOXY resin you have to work quickly, brush on a layer of mixed epoxy in the glass panel and steel seam area about 2" wide, lay down a strip of fiberglass mat about 1" wide half on the steel/half on the glass plug, then using your brush, daub EPOXY resin on to the fiberglass mat to saturate the mat fibers, no strokes, daubing, strokes will pull up the mat fibers and make a mess, do this all the way around the outer perimeter, if you move quick enough, you can add another layer of mat/resin directly ontop of the previous layer, depending on what OZ weight mat you purchase (I recommend 1.5 oz) 3 layers should be enough, then do the same to the under side from inside the rear window, bond the plug flanges and steel to each other fully, the backside you can add a lot more resin/mat build up, the outside you'll be dressing down, use no bondo to finesse your outer panel, if you must fill sanding/grinding marks/small pits, or build an area up use USC Duraglas polyester filler,...I've done alot of fiberglass body panels over the years on Vettes as well as flares/IMSA panels/etc on steel bodied cars, so I've learned the hard way what works, and what doesn't......but in the end, regardless of how rigid you make a steel body so it won't flex with fiberglass panels/inserts/plugs/etc the co-effiecient properties between steel and fiberglass are so vastly different, that it will eventually crack, even fiberglass to fiberglass bonds eventually telegraph or break, fiberglass components are only their strongest when they are in one piece....steel and fiberglass are not a happy marriage

Mike

[Daytona R/T SE]

I'm converting my charger to a daytona using a Janak kit
Can a fiberglass plug be fitted with out cracking.

If your going to go with the fiberglass plug, which IMHO and from experience will EVENTUALLY crack at the bond sites, best thing to do BEFORE you put the plug in is: welded in frame connectors, the type that pass thru the floor, weld/re weld every inch of the unibody, not continuous welds, but improve upon the factory spaced welds in quality, as these cars were haphazardly welded on the line, when you install the plug were the "lips" contact the inner sail panels, 24-36 grit finish on both the steel and the glass for tooth, do not use SMC, or similar Vette panel adhesive, use Marson MarGlas long strand polyester filler, but fit the panel first, use screws to align the panel flanges to the sail panels, that will give you a go-no go fit when you are in a hurry before the MarGlas set-ups (15mins), so lather the panels flanges up, you and an assistant quickly install the panel, don't draw the screws too tight, let it set up for a day or so, then remove the screws, then use a flap wheel, 24-36 grit to put a bevel/taper around the outer sides and top of the panel, as well as put some tooth on the surrounding steel, then use an EPOXY fiberglass resin and MAT (not cloth), with EPOXY resin you have to work quickly, brush on a layer of mixed epoxy in the glass panel and steel seam area about 2" wide, lay down a strip of fiberglass mat about 1" wide half on the steel/half on the glass plug, then using your brush, daub EPOXY resin on to the fiberglass mat to saturate the mat fibers, no strokes, daubing, strokes will pull up the mat fibers and make a mess, do this all the way around the outer perimeter, if you move quick enough, you can add another layer on mat/resin directly ontop of the previous layer, depending on what OZ weight mat you purchase (I recommend 1.5 oz) 3 layers should be enough, then do the same to the under side from inside the rear window, bond the plug and flanges to each other fully, the backside you can add a lot more resin/mat build up, the outside you'll be dressing down, use no bondo to finesse your outer panel, if you must fill sanding/grinding marks/small pits, or build an area up use USC Duraglas polyester filler,...I've done alot of fiberglass body panels over the years on Vettes as well as flaes/IMSA panels/etc on steel bodied cars, so I've learned the hard way what works, and what doesn't......but in the end, regardless of how rigid you make a steel body so it won't flex with fiberglass panels/inserts/plugs/etc the co-effiecient properties between steel and fiberglass are so vastly different, that it will eventually crack, even fiberglass to fiberglass bonds eventually telegraph or break, fiberglass components are only their strongest when they are in one piece....

Mike

Good information, Mike.  

And...

I'd like to add...

It would be a good idea to reinforce the drip channel area of the fiberglass plug where it meets the front of the trunk lid.

When test fitting my fiberglass plug to my car, prior to giving up on it and going with my steel plug,

I noticed the plug in the drip channel area flexed a LOT when I closed my trunklid against it with the weather stripping in place.

I think a piece of 3/4 inch square steel tubing formed to fit the underside of the plug, bonded to the fiberglass, and welded to the car's structure should do the trick.

[BigBlockSam]

welded in frame connectors, the type that pass thru the floor, weld/re weld every inch of the unibody,

a must on any daytona clone , whether you go steel or fiberglass . old tired uni bodies flex a lot . 

Hi Mike!

[Mike DC]

      
 
IMHO subframe connectors shouldn't be cut through the floor in most street car cases.  


SC's are not the be-all-end-all in stiffening a unibody.  The area between the subframes may be the weakest link on a stock body, but it only helps to stiffen the weakest link until it isn't the weakest link anymore.  After that, the flex point moves somewhere else.  Beefing up the SCs farther is just hacking up the car & adding weight.  



XV Motorsports already did the research & experimenting on stiffening these unibodies for us.  We might as well learn from them.  They did the original chassis R&D a whole lot better than they ever did customer service.  

They went with floor-fitting (US Car Tool type) connectors + factory style torque box plating + a lower radiator brace.  The next thing they did was tie the shock towers to the firewall/doorjambs better.  Some convertibles even got one more additional brace on the rear subframe (not sure where).  But XVM never went through the floor with the subframe connectors.